EFFECT OF SEASON 295 



tained for an indefinite period, since any further response 

 is impossible after the full erection of the organ. It is 

 therefore more practical to begin with it a few degrees 

 below the horizon, and continue the record till it rises to 



Fig. 17T. Geotropic curve : (a) of a spring-, and (b) of a winter- 

 specimen. The latent period of the former is in the present 

 case 6 minutes, of the latter 48 minutes. 



Note the relatively erect curve of the spring-specimen, indicating 

 a more intense geotropic reaction (Tropaeolum). 



Time-interval between dots 3 minutes. 



the same angle above the horizontal position. The slope 

 of the curve is then found to remain practically uniform 

 for about half an hour, which is more than sufiicient for 

 the completion of an experiment on the action of the 

 anaesthetic. The effect of anaesthetics will be described 

 not only on the growing but also on the pulvinated 

 organ. 



